Donor lymphocyte infusion (DLI) has some benefit effects as graft-versus-leukemia effect, reducing the relapse of leukemia and inducing of a complete remission. But it has also a graft-versus-host-disease (GVHD) effect. So it is required a proper marker test when DLI is performing. The DNA chimerism analysis can be a marker test in DLI. Variable number of tandem repeats (VNTR) are highly polymorphic DNA markers in the human genomic DNA and used as primers of DNA chimerism analysis. A 43-year-old male who had been diagnosed acute myelogenous leukemia was transplanted with allogeneic peripheral blood stem cells. The initial chimerism analysis showed complete chimerism but it changed to mixed chimerism after 7 months of transplantation. We predicted the relapse of leukemia and performed DLI. The patient could obtain the complete chimerism after DLI. We report a case of chimerism analysis which was useful to predict the relapse of leukemia and perform the DLI.